CVE-2025-12978
Nov. 25, 2025, 10:16 p.m.
5.4
Medium
Description
Fluent Bit in_http, in_splunk, and in_elasticsearch input plugins contain a flaw in the tag_key validation logic that fails to enforce exact key-length matching. This allows crafted inputs where a tag prefix is incorrectly treated as a full match. A remote attacker with authenticated or exposed access to these input endpoints can exploit this behavior to manipulate tags and redirect records to unintended destinations. This compromises the authenticity of ingested logs and can allow injection of forged data, alert flooding and routing manipulation.
Product(s) Impacted
| Vendor | Product | Versions |
|---|---|---|
| Fluent |
|
|
Weaknesses
Common security weaknesses mapped to this vulnerability.
*CPE(s)
Affected systems and software identified for this CVE.
| Type | Vendor | Product | Version | Update | Edition | Language | Software Edition | Target Software | Target Hardware | Other Information |
|---|---|---|---|---|---|---|---|---|---|---|
| a | fluent | bit | / | / | / | / | / | / | / | / |
| a | fluent | bit | in_http | / | / | / | / | / | / | / |
| a | fluent | bit | in_splunk | / | / | / | / | / | / | / |
| a | fluent | bit | in_elasticsearch | / | / | / | / | / | / | / |
References
Tags
CVSS Score
CVSS Data - 3.1
- Attack Vector: NETWORK
- Attack Complexity: LOW
- Privileges Required: LOW
- Scope: UNCHANGED
- Confidentiality Impact: NONE
- Integrity Impact: LOW
- Availability Impact: LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
Timeline
Published: Nov. 24, 2025, 3:15 p.m.
Last Modified: Nov. 25, 2025, 10:16 p.m.
Last Modified: Nov. 25, 2025, 10:16 p.m.
Status : Awaiting Analysis
CVE has been recently published to the CVE List and has been received by the NVD.
More infoSource
cret@cert.org
*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.